Comparison of calorimetric methods for the assessment of slag cement hydration

This study aims to contribute to future-proofing the supply of cement powders for the UK’s nuclear waste cementation program, by enabling rapid and reliable assessment of heat evolution from candidate grout formulations. Isothermal conduction calorimetry and semi-adiabatic calorimetry experiments were carried out at room temperature, to monitor the heat of hydration of blended blast furnace slag (BFS)-Portland cement formulations of relevance for wasteform grout applications. By changing the particle size distribution of the BFS, the physical and chemical properties of the cement grout are altered, and this can be monitored and understood through comparison between the two calorimetry methods

EFFECTS OF JOINT PRODUCT MANAGEMENT STRATEGIES ON E.COLI 0157:H7 AND FEEDLOT PROFITS

The objective of this study was to determine the effect of Escherichia coli 0157:H7 on feedlot profits. Fecal samples from 711 feedlot pens in 73 feedlots in Nebraska, Kansas, Oklahoma, and Texas were tested for E. coli 0157:H7. Average daily gain and feed-to-gain ratios were computed for each feedlot pen, and managers from each feedlot provided information on various feedlot management practices. Cattle performance and E. coli 0157:H7 prevalence are both affected by feedlot management practices. The indirect effect of E. coli 0157:H7 on potential feedlot profits was determined by measuring the effects of management practices on E. coli 0157:H7 levels and cattle performance. Management practices that affect cattle performance were identified using ordinary least squares regressions. A negative binomial regression was used to identify management practices that affect E. coli 0157:H7 prevalence. Certain feedlot management practices were identified that have a joint impact on cattle performance and E. coli 0157:H7 prevalence. Using predatory insects to control flies, controlling for stray dogs, foxes, and coyotes in feed areas, removing manure from pens during finishing, and including tallow in the ration were management strategies associated with higher feedlot profits and lower E. coli 0157:H7 prevalence. Using mobile sprinklers for dust control and including alfalfa or sorghum hay or silage in the ration were associated with lower E. coli 0157:H7 prevalence and lower feedlot profits. Increasing days between cleaning water tanks and restricting movement of horses were associated with higher feedlot profits and higher E. coli 0157:H7 levels. Controlling for stray cats in feed areas and including liquid protein in the ration were associated with lower feedlot profits and higher E. coli 0157:H7 levels. These specific management strategies, which were not robust through a sensitivity analysis, should be interpreted with caution. The general categories of management strategies, however, were robust and consistent with past researchLivestock Production/Industries,

High efficiency carbonate fuel cell/turbine hybrid power cycle

The hybrid power cycle studies were conducted to identify a high efficiency, economically competitive system. A hybrid power cycle which generates power at an LHV efficiency > 70% was identified that includes an atmospheric pressure direct carbonate fuel cell, a gas turbine, and a steam cycle. In this cycle, natural gas fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming fuel. The mixed gas then flows to a direct carbonate fuel cell which generates about 70% of the power. The portion of the anode exhaust which is not recycled is burned and heat transferred through a heat exchanger (HX) to the compressed air from a gas turbine. The heated compressed air is then heated further in the gas turbine burner and expands through the turbine generating 15% of the power. Half the exhaust from the turbine provides air for the anode exhaust burner. All of the turbine exhaust eventually flows through the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Exhaust from the cathodes flows to a steam system (heat recovery steam generator, staged steam turbine generating 15% of the cycle power). Simulation of a 200 MW plant with a hybrid power cycle had an LHV efficiency of 72.6%. Power output and efficiency are insensitive to ambient temperature, compared to a gas turbine combined cycle; NOx emissions are 75% lower. Estimated cost of electricity for 200 MW is 46 mills/kWh, which is competitive with combined cycle where fuel cost is > $5.8/MMBTU. Key requirement is HX; in the 200 MW plant studies, a HX operating at 1094 C using high temperature HX technology currently under development by METC for coal gassifiers was assumed. A study of a near term (20 MW) high efficiency direct carbonate fuel cell/turbine hybrid power cycle has also been completed

Instant luminescence chronologies? High resolution luminescence profiles using a portable luminescence reader

Establishing a robust chronology is fundamental to most palaeoenvironmental studies. However, the number and positioning of dated points is critical. Using a portable luminescence reader, it is possible to rapidly generate high resolution down core relative age profiles. Profiles of portable luminescence data from two coastal dunes were evaluated and compared with the results of particle size analysis, stratigraphy, and an independent historical chronology. Results show that, even in young samples, portable luminescence data is dominated by an age related signal which in homogeneous sediment need not be corrected for moisture, feldspar content changes or grain size. Profiles therefore provide relative chronologies from which accumulation phases can be established, and from which better targeted sampling and comparison to other sites could be undertaken. Even though they do not provide instant absolute chronologies, field-based portable luminescence profiling of Late Quaternary sites hold much potential to improve the resultant chronologies

Oxygenator safety evaluation: A focus on connection grip strength and arterial temperature measurement accuracy

This report describes the assessment of three specific safety-related specifications in the consideration of an alternate oxygenator; first the grip strength relationship between various oxygenator connectors and SMARxT tubing, second, the grip strength of various biopassive tubings and an isolated SMARxT connector, and finally, the accuracy of the arterial outlet temperature measurement. Grip strength experiments for the connections between the SMARxT tubing and the venous reservoir outlet and the oxygenator venous inlet and oxygenator arterial outlet of the Medtronic Affinity, Sorin Synthesis, Sorin Primox, and Terumo Capiox RX25 oxygenators were performed. In addition we compared the grip strength of polyvinyl chloride, Physio, Trillium, Carmeda, X-Coating, and SMARxT tubing. The accuracy of the integrated arterial outlet temperature probes was determined by comparing the temperatures measured by the integrated probe with a precision reference thermometer. Connector grip strength comparisons for the evaluation oxygenators with SMARxT tubing showed significant variation between oxygenators and connections (p = .02). Evaluation of the arterial outlet showed significant variation between evaluation oxygenators, while at the venous reservoir outlet and oxygenator inlet, there were no significant differences. Grip strength comparison data for the various tubing types demonstrated a main effect for tubing type F(5, 18) = 8.01, p = .002, eta(p)(2) = .77. Temperature accuracy measurements demonstrated that all oxygenators overread the arterial outlet temperature at 15 degrees C, whilst at temperatures > or = 25 degrees C, all oxygenators underread the arterial outlet temperature. The integrity of SMARxT tubing connection is influenced by the connector type, and may decline over time, highlighting the importance to not consider interchanging components of the bypass circuit as inconsequential.Richard F. Newland, Robert A. Baker, Andrew J. Sanderson, Sigrid C. Tuble, Phil J. Tull

The large longitudinal spread of solar energetic particles during the January 17, 2010 solar event

We investigate multi-spacecraft observations of the January 17, 2010 solar energetic particle event. Energetic electrons and protons have been observed over a remarkable large longitudinal range at the two STEREO spacecraft and SOHO suggesting a longitudinal spread of nearly 360 degrees at 1AU. The flaring active region, which was on the backside of the Sun as seen from Earth, was separated by more than 100 degrees in longitude from the magnetic footpoints of each of the three spacecraft. The event is characterized by strongly delayed energetic particle onsets with respect to the flare and only small or no anisotropies in the intensity measurements at all three locations. The presence of a coronal shock is evidenced by the observation of a type II radio burst from the Earth and STEREO B. In order to describe the observations in terms of particle transport in the interplanetary medium, including perpendicular diffusion, a 1D model describing the propagation along a magnetic field line (model 1) (Dr\"oge, 2003) and the 3D propagation model (model 2) by (Dr\"oge et al., 2010) including perpendicular diffusion in the interplanetary medium have been applied, respectively. While both models are capable of reproducing the observations, model 1 requires injection functions at the Sun of several hours. Model 2, which includes lateral transport in the solar wind, reveals high values for the ratio of perpendicular to parallel diffusion. Because we do not find evidence for unusual long injection functions at the Sun we favor a scenario with strong perpendicular transport in the interplanetary medium as explanation for the observations.Comment: The final publication is available at http://www.springerlink.co

Toward a Self-Updating Platform for Estimating Rates of Speciation and Migration, Ages, and Relationships of Taxa.

Rapidly growing biological data-including molecular sequences and fossils-hold an unprecedented potential to reveal how evolutionary processes generate and maintain biodiversity. However, researchers often have to develop their own idiosyncratic workflows to integrate and analyze these data for reconstructing time-calibrated phylogenies. In addition, divergence times estimated under different methods and assumptions, and based on data of various quality and reliability, should not be combined without proper correction. Here we introduce a modular framework termed SUPERSMART (Self-Updating Platform for Estimating Rates of Speciation and Migration, Ages, and Relationships of Taxa), and provide a proof of concept for dealing with the moving targets of evolutionary and biogeographical research. This framework assembles comprehensive data sets of molecular and fossil data for any taxa and infers dated phylogenies using robust species tree methods, also allowing for the inclusion of genomic data produced through next-generation sequencing techniques. We exemplify the application of our method by presenting phylogenetic and dating analyses for the mammal order Primates and for the plant family Arecaceae (palms). We believe that this framework will provide a valuable tool for a wide range of hypothesis-driven research questions in systematics, biogeography, and evolution. SUPERSMART will also accelerate the inference of a "Dated Tree of Life" where all node ages are directly comparable. [Bayesian phylogenetics; data mining; divide-and-conquer methods; GenBank; multilocus multispecies coalescent; next-generation sequencing; palms; primates; tree calibration.]

The evolution of language: a comparative review

For many years the evolution of language has been seen as a disreputable topic, mired in fanciful "just so stories" about language origins. However, in the last decade a new synthesis of modern linguistics, cognitive neuroscience and neo-Darwinian evolutionary theory has begun to make important contributions to our understanding of the biology and evolution of language. I review some of this recent progress, focusing on the value of the comparative method, which uses data from animal species to draw inferences about language evolution. Discussing speech first, I show how data concerning a wide variety of species, from monkeys to birds, can increase our understanding of the anatomical and neural mechanisms underlying human spoken language, and how bird and whale song provide insights into the ultimate evolutionary function of language. I discuss the ‘‘descended larynx’ ’ of humans, a peculiar adaptation for speech that has received much attention in the past, which despite earlier claims is not uniquely human. Then I will turn to the neural mechanisms underlying spoken language, pointing out the difficulties animals apparently experience in perceiving hierarchical structure in sounds, and stressing the importance of vocal imitation in the evolution of a spoken language. Turning to ultimate function, I suggest that communication among kin (especially between parents and offspring) played a crucial but neglected role in driving language evolution. Finally, I briefly discuss phylogeny, discussing hypotheses that offer plausible routes to human language from a non-linguistic chimp-like ancestor. I conclude that comparative data from living animals will be key to developing a richer, more interdisciplinary understanding of our most distinctively human trait: language